It is known that metalized PET films provide optimal solution for high oxygen and general gas barrier levels, aroma and flavor retention. The metallization of PET film also results in significant improvement in water vapor barrier. Metalized PET film is proven to achieve special optical properties or a metal look for decorative applications in diffusion of gases and flavor through the film. Although metalized PET film market continues to grow, there are no established sustainable solutions to recover and recycle post-consumer and postindustrial metalized PET films waste or any application of this material. While PET recycling industry has been established for several decades and accepted as the most leading recycled material, metalized PET films are discarded as waste and ends up in the landfill. The growing consumer awareness towards recycling of plastics demands requires creativity in recycling of metalized PET films and its subsequent suitable applications. There are no known commercially existent metalized PET films recycling facilities in the world.
In order to increase the life cycle and reduce the carbon footprint, metalized PET films needs to be recycled effectively and efficiently. However, there are numerous issues that make recycling of PET films difficult. The intrinsic viscosity (also known as I.V.) of metalized PET film is typically less than 0.6 dl/g making it unsuitable for many applications such as sheet extrusion/thermoforming and mono filament yarn after recycling. Mechanical properties of PET films with 0.6 dl/g are very inferior and consequently limit its potential application after recycling. The color and clarity of recycled metalized film poses challenges in clear applications. The increased haze and B value (yellowness) of metalized PET film makes it unattractive for most applications.
Unlike, PET bottles recycling, there are no established collection centers or material recovery facilities for PET films. Secondly, lack of consumer education, awareness and consequent participation for the recyclability of metalized films makes it difficult to be collected and recycled even from an industrial source. The absence of definitive and desired sources for collection of metalized PET films makes a poor business case for the technology to be designed for this material.                The other reason for lack of Metalized PET film includes unknown science of washing Metalized PET films. The use of conventional PET recycling techniques, including hot washing with proven alkaline cleaners, de-foamer additives and other additives are yet to be proven effective for washing and removing Aluminum layer and other contaminates from Metalized PET films. The effect of such additives and washing methods is unknown in public domain.In view of the above-said challenges and keeping environment safety into consideration the applicant of the present invention comes out with a process for converting used/waste metalized PET film into recycled PET as a starting raw material for various utility products. Hence, an environmental friendly process for recycling of metalized PET film is developed to produce recycled PET pellets with enhanced physical, mechanical, optical and aesthetic properties. The physical, mechanical and aesthetic properties of the straps, yarn, and sheet as produced from the recycled metalized PET are comparable to virgin PET pellets used for the same application. This is evident from the Table 6 & 7.        